What is the primary purpose of a fire department connection (FDC) in a sprinkler system?

The primary purpose of a fire department connection (FDC) in a sprinkler system is to provide additional water supply for firefighting. This connection allows firefighters to supplement the water supply of the sprinkler system during an emergency situation. By connecting their hoses to the FDC, firefighters can ensure that there is adequate water pressure and volume available to effectively combat a fire, especially in larger buildings where the existing sprinkler system might not be sufficient on its own.

This feature is crucial because it enhances the firefighting capabilities available on-site, making it easier to control and extinguish fires before they spread and cause further damage. Fire department connections are typically located at accessible points outside the building to facilitate rapid deployment by responding personnel.

Other options, while related to the operation of a fire protection system, do not capture the primary role of the FDC. The alarm system activation and system pressure control are functions that occur within the system itself or provide notifications rather than directly contribute to the active firefighting process. Draining the system is necessary for maintenance but does not relate to the fundamental purpose of the FDC during a fire event.